Even though it is 2020 I still use Photoshop CS2. So this may be out of date for your needs. For Photoshop CC I recommend: WikiHow

First Option

1. Simply put the .ABR file in "C:\Program Files\Adobe\Adobe Photoshop CS2\Presets\Brushes"

Second Option

1. Open Photoshop.
2. Go to your brushes and click the arrow for the menu.
3. Choose "Load Brushes".